Monica,

I think you have the right idea from what you have explained. If the 4 heads worked fine before and then after adding 2 more didn't work. It would most likely be a flow or pressure problem or both. You didn't mention if he did any design calculations before giving you the advice but I assume he was wagging it. You can do this if you would like. Before undertaking any more changes in your system, first get your mainline pressure and flow rate (gpm) for your system. If your landscaper has already done this he can give you his findings. If you would like to know how to do this I can help you. I need to know how your system is hooked up to the water supply. Is your irrigation hooked up via your house outside faucet or directly to the main water feed to your house? In other words is your irrigation taking off water before or after your house regulator?

To actually answer your question you have to add another leg to your valve manifold set up including wiring to the controller and all the piping that goes from the new valve to the new zone heads. Is your existing system a new or old installation? Aloha

lehua13,
yes, the (6) spray heads were working just fine before he added another spray head and a mp rotator. The system was installed last summer. I normally don't water during the peak hours for environmental purposes as well as a courtesy to others on the community well. But, even when I did (if I were testing for adjustment) I never had a pressure issue. The installer that put in the 2 new sprinklers is not the one that designed and installed the system. That guy is out of business. Just as well. I wouldn't have wanted him back out here again anyway. Your assumption is correct...the new guy was "wagging it". I've got a call into my plumber to check which side of the pressure regulator he installed in Jan the sprinkler system is on. The system feeds off the main line from the street. WE (plumber and I) are positive he installed the pressure regulator AFTER the sprinklers so that they would get the benefit of the higher pressure. My husband thinks the sprinklers were included in the reduced pressure. He's wrong (g) but for his peace of mind we're checking it out. Our water pressure was reading 85 (to upper 90s at times). It was causing some problems in the house so we had the regulator installed. The line from the road is 1 1/2". I don't have any idea what the system's pvc size is but pressure has never been a problem and still isn't on the other 5 zones. I remember the installer even remarking how good our water pressure was.
Also, I don't understand how/why tapping or lightly touching and holding the top of these mp rotators will cause one that isn't spraying correctly, to work properly. About an hour ago, I turned them on, expecting to see them just dribbling. They were ALL spraying like they should :o
Walked in the house to get my camera and when I came back outside, 4 of them had decreased to where they were throwing water about 12" or less. The others were showing signs of low pressure too. I could tap or hold down the tops and they'd work again, then the spray would be reduced again. It's a thing of beauty when they're all working properly tho! :) Plumber mentioned a possible"solenoid" problem?? He's not a sprinkler expert tho.
Thanks,
Monica

Monica,

What is make and model of heads? What is your flow rate(fill 5-gallon bucket and time the fill)? Pressure, if that high 90-100 psi, may cause your irrigation heads and valves problems. Your heads have a design range for normal street pressure of about 60 to 80 psi. The literature on the heads tell you the pressure range for the distance of coverage. I can find it on the internet if I know your type, make and model of head. You may have to get a pressure regulator for your irrigation system as well and get the pressure into the normal operating range(also reduce possible water hammer). You are lucky, it is easier to reduce pressure than have to boost it up. The 1 1/2 line is large for a house also a good thing(reduces noise).